When it comes to fermenting food and drinks, the quality of your water is important. The water you choose to use for your fermenting projects plays a big role in what your final product will be.
When fermenting at home, most people reach for the tap on the kitchen sink. It’s convenient and a pretty reliable source. However…
Here are some things to keep in mind when using tap water for fermenting:
If your water source is a private well than you are in charge of the quality of your water. You should consider having your well water tested every year to check for contamination. And most well water is higher in minerals, which is fine for most fermenting projects. For example, water kefir loves minerals (in fact, some people add trace minerals to their water kefir). However, you do need to be mindful of having too many minerals. Kombucha SCOBYs don’t care for high mineral content and may break down over time if exposed to too high of mineral counts.
If your water comes from a municipal source, you need to be concerned with added chlorine, chloramine, and fluoride. You can request a report from your local water utility to find out exactly what it contains. I haven’t requested a report, but I can smell the chlorine in my tap water. This is an easy indicator to me that I shouldn’t use it straight from the tap for fermenting. Chlorine, chloramine, and fluoride can all inhibit the fermentation process. And it can also alter the taste of fermented drinks like water kefir and kombucha.
You will also need to take notice if your water is hard or soft. Hard water may be an indication that your tap water is high in minerals. If it’s soft or treated with a water softer, it may be too low in minerals.
So, a few ways to make your tap water more fermentation friendly:
- Filter the water with an activate charcoal filtration system. I use a BRITA pitcher and filter, which is said to reduce chlorine taste and odor, zinc, and even contaminant’s like copper, mercury and cadmium.
- Boiling your water for 20 minutes may evaporate the chlorine.
- Pour water into a bowl and let sit on the counter overnight. This will may also evaporate chlorine.
If you still notice problems with your ferment projects going very slowly or not working at all. It may be time to find another water source.
Spring Water

This is my spring water source in the dead of winter!
I predominately use spring water for my fermented food and drinks and I am lucky enough to live less than an hour from a spring. You can search for a spring water source near you on the Find A Spring website. I have a couple 5 gallon refillable jugs that I fill whenever I happen to be in the area of the spring. Admittedly, I have no idea what’s in there. But there is generally a line of people waiting to fill their bottles at the spring and the water tastes great. 🙂
Distilled Water
Distilled water is up for debate in my book. Distilled water is completely purified and is said to contain no minerals, contaminants, or additives (like chloramine). I have tested and distilled water appears to work fine for vegetable ferments, but isn’t a good choice water kefir. If used for water kefir, you will need to add trace minerals to your brewing process. Most grocery stores have refillable water filling stations and this is usually distilled water.
So, what does this all mean?
It means there is not a perfect water choice.
It means certain water sources work better for certain ferments.
It means you should take care to remove chlorine, chloramine, and fluoride as best you can before using tap water.
And finally, experimentation is key. I had no idea my water kefir grains like minerals, but by substituting spring water for tap water for a few brewing cycles, it became very apparent to me. In the form of bigger and happier grains!
Remember, fermenting DOES NOT require you to be perfect. If you forget to filter your tap water every once in awhile, you are not going to kill your kombucha SCOBY. Simply do what you can to keep your fermenting projects happy!
This is such useful information! We have our own private well, so that’s nice 🙂
Yay! That’s awesome!
If you started with tap water can you pour it out and put another water source in it and start over. Started first sauerkraut 2 days ago.
Thanks in advance!
Unfortunately, I don’t have any experience doing that so I can’t say for sure. I would let it go as is. If you don’t see any bubbles in the next couple of days then consider starting another batch. If you do see some bubbles, you are good to go.
Most grocery stores that I’ve seen use municipal water then run it through a big RO system for their water stations.
I’m brining without a scale & wondering how to measure fine ground Real Salt to a liter of water?